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Finding the Fourth Proportional to 669.32, 923.78 and 389.53

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Solution

The fourth proportional to 669.32, 923.78 and 389.53 is: 537.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.32 : 923.78 = 389.53 : x
  2. Step 2: Convert to fraction form
    669.32/923.78 = 389.53/x
  3. Step 3: Cross multiply
    669.32x = 923.78 × 389.53
  4. Step 4: Simplify right side
    669.32x = 359,840.02
  5. Step 5: Solve for x
    x = 359,840.02/669.32
  6. Step 6: Final answer
    x = 537.62

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.